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    <title>Document</title>
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    <script>
        // var arr = [1, 2, 3, 4, 5];
        // // 
        // var res = arr.every(function (item) {
        //     return item - 2;   //-1  0  1  2  3 
        // })

        // console.log(res)



        var arr = [1, 2, 3]
        var arr1 = [4, 5, 6]
        var res = arr.concat(arr1)
        console.log(arr, arr1)
        console.log(res)
    </script>
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